Allocasuarina decussata

Life-forms

Classification System: APG IV

Superregnum: Eukaryota
Regnum: Plantae
Cladus: Angiosperms
Cladus: Eudicots
Cladus: Core eudicots
Cladus: Rosids
Cladus: Eurosids I
Ordo: Fagales

Familia: Casuarinaceae
Genus: Allocasuarina
Species: Allocasuarina decussata
Name

Allocasuarina decussata (Benth.) L.A.S.Johnson, J. Adelaide Bot. Gard. 6: 75 (1982).
Synonyms

Basionym
Casuarina decussata Benth., Fl. Austral. 6: 200 (1873).

Distribution
Native distribution areas:
Allocasuarina decussata

Continental: Australasia
Regional: Australia
Western Australia (Blackwood R. south to Denmark)

References: Brummitt, R.K. 2001. TDWG – World Geographical Scheme for Recording Plant Distributions, 2nd Edition
References
Primary references

Johnson, L.A.S. 1982. Notes on Casuarinaceae II. Journal of the Adelaide Botanic Gardens 6(1): 73–88. JSTOR PDF Reference page. : 6: 75.

Links

Govaerts, R. et al. 2019. Allocasuarina decussata in World Checklist of Selected Plant Families. The Board of Trustees of the Royal Botanic Gardens, Kew. Published online. Accessed: 2019 Sep 28. Reference page.
International Plant Names Index. 2019. Allocasuarina decussata. Published online. Accessed: Sep 28 2019.
Tropicos.org 2019. Allocasuarina decussata. Missouri Botanical Garden. Published online. Accessed: 28 Sep 2019.
USDA, ARS, Germplasm Resources Information Network. Allocasuarina decussata in the Germplasm Resources Information Network (GRIN), U.S. Department of Agriculture Agricultural Research Service. Accessed: 07-Oct-06.

Allocasuarina decussata, commonly known as karri oak[2] or karri she-oak,[3] is a medium-sized tree, or more rarely a shrub, that is endemic to the south west of Western Australia. It is an understory tree in karri forest but also occurs as a stunted shrub in places like Bluff Knoll in the Stirling Range.
Contents

1 Description
2 Taxonomy
3 Distribution and habitat
4 Cultivation and uses
5 References

Description

Karri oak usually grows as a medium tree 8–15 m (26–49 ft) high, although in harsh, exposed situations in places like the top of Bluff Knoll it is a stunted shrub or poorly-formed tree in shrubland. As with other members of the family Casuarinaceae, the foliage consists of wiry green branchlets called cladodes with rings of minute leaf scales. In this species, the branchlets are about 140 mm (5.5 in) long, roughly square or X-shaped in cross section, with four scale-teeth in each ring. The rings of scale-leaves are 7–9 mm (0.28–0.35 in) apart. Separate male and female flowers form on the same individual plant. The fruiting structure is a woody cone, shaped like a short cylinder with its diameter roughly equal to or slightly greater than its length. The fruit is a winged samara 7–9 mm (0.28–0.35 in) long.[4] It often grows in association with Acacia pentadenia[2] and Asplenium aethiopicum often grows as an epiphyte on its branches.[4]
Taxonomy

This species was first formally described in 1873 by George Bentham Flora Australiensis from specimens collected by James Drummond near Cape Riche, Western Australia. Bentham gave it the name Casuarina decussata.[5][6] In 1982, Lawrie Johnson moved it to its current genus Allocasuarina in his revision of the she-oaks.[7] It is closely related to A. torulosa of New South Wales and Queensland.[2]
Bark of a young A. decussata in the Walpole-Nornalup National Park.

The specific epithet (decussata) is a Latin word meaning "like the letter X" or "the Roman numeral ten".[8]
Distribution and habitat

Karri oak is restricted to the southwest of Western Australia in the Esperance Plains, Jarrah Forest and Warren biogeographical regions. It grows on loam in the karri forest but also found on much poorer soils in the Stirling Range.[3]
Cultivation and uses

Karri oak is not known in cultivation and there is only limited availability of timber because most trees are in national parks but its pale reddish-brown heartwood has distinctive rays that potentially make it useful as a craft wood.[2]
References

"Allocasuarina decussata". Australian Plant Census. Retrieved 7 January 2020.
"Karri oak". Forest products commission Western Australia. Retrieved 29 January 2015.
"Allocasuarina decussata (Benth.) L.A.S.Johnson". FloraBase. Western Australian Government Department of Biodiversity, Conservation and Attractions.
Wilson, Karen Louise; Johnson, Lawrence A.S. (1989). Flora of Australia (Volume 3) (PDF). Canberra: Australian Government Publishing Service. pp. 142–143. Retrieved 7 January 2020.
"Casuarina decussata". APNI. Retrieved 7 January 2020.
"Flora australiensis:a description of the plants of the Australian territory /by George Bentham, assisted by Ferdinand Mueller". Biodiversity Heritage Library. pp. 200–201. Retrieved 30 January 2015.
"Allocasuarina decussata". APNI. Retrieved 7 January 2020.
Brown, Roland Wilbur (1956). The Composition of Scientific Words. Washington, D.C.: Smithsonian Institution Press. p. 255.